Roll mill



Dec. 24, 1935. K. G. HELLNER ET AL 2,025,348

ROLL MILL Filed June 15, 1933 2 Sheets-Sheet l gwucwvbo'm Karl GaHBZ ner,

Dec, 24, 17935. K L N ET AL 2,625,348

TOLL MILL Filed June 15, 1933 2 Sheets-Sheet 2 Patented Dec. 24, 1935 PATENT OFFICE ROLL IVHLL Karl Gustaf Hellner and Axel Gustaf Johansson, Nalden, Sweden Application June 15, 1933, Serial No. 676,020 In Sweden June 22, 19353 2 Claims.

For the separation of water from highly watery material, roller presses have been used for a long time, in connection with which presses the watery material is fed between press rollers bearing on each other in pairs. It is important in the carrying out of this process that the water separated during the pressing operation be removed quickly enough to prevent it from being entrained between the rollers, since otherwise the water will again combine with the pressed material when the latter has passed through the press zone. To accelerate the discharge of water, the press rollers have been arranged vertically, that is to say rotatably on vertical axes in order thus to utilize the vertical rapid downflow of the water. The rollers have also been provided with channels intended to take up the water and to promote the discharge thereof. These channels have been extended transversely or parallel with respect to the roller axes and for this reason have been incapable of aiding toward a free downward flow of the water in a sufi'icient degree. Instead, the transverse channels have to a certain extent prevented the discharge, the parallel channels having had an entraining efiect on the water separated in each channel, so that the water would be entrained through the press zone to be again mixed with the pressed material.

The present invention aims at an arrangement of the recesses 01 channels of the press rollers in such a manner that they will not only promote a quick downward discharge of the separated water, but will at the same time quickly remove the water laterally out of the press zone, so that the water will not have time during the rotation of the rollers to enter the press zone or to pass therethrough.

The arrangement according to the invention is principally characterized in that the recesses, grooves or channels of the press rollers are arranged in such a manner as to extend obliquely downwardly and outwardly on both sides of the press zone, on the feeding-in side of the rollers and from the press zone between the rollers.

The arrangement is preferably constructed so that the rollers are provided with helically extending channels, one roller having right-handed and the other left-handed channels with respect to the press zone. By adapting the pitch of the channels relatively to the speed at which the rollers rotate, the separated water may, according as it accumulates, be conveyed outwardly on both sides of the press zone, so that it will not have time to enter the press zone or to pass therethrough before it has left the rollers entirely through the downward flow.

The accompanying drawings illustrate a few embodiments of the invention, Figs. 1-5 being diagrammatic representations thereof. 5

Fig. 1 shows in elevation two rollers cooperating in pairs.

Fig. 2 is a sectional view taken substantially along the line 22 of Figure 3.

Fig. 3 shows the pair of rollers with the feed 10 hopper viewed from above.

Fig. 4 shows two pairs of rollers arranged according to Figs. 1 and 2, both pairs having feed hoppers arranged one above the other, so that material treated by the upper pair may be transferred directly to the lower pair of rollers to be further treated by the latter.

Fig. 5 shows three press rollers cooperating with each other, as viewed from above, two of which rollers are connected to a feed hopper and 20 cooperate in a pair in the same manner as the rollers shown in Figs. 13, while between the third roller and one of the rollers in the firstmentioned pair of rollers is provided a device for the introduction of the treated press material 25 in between said third roller and the intermediate roller cooperating therewith.

Fig. 6 is a front elevation of the machine viewed from the feeding-in side of an embodiment adapted for practical use.

Fig. 7 shows the machine as viewed from the one' end and in section on line in Fig. 6. g

The rollers I may be actuated either by spring pressure or by hydraulic pressure so as to bear on each other as tightly as possible. the one roller of the pair of rollers is then journalled in fixed bearings and the other roller in displaceable bearings, which latter are actuated either by springs or hydraulically.

Both rollers are provided with channels 2. These channels are in each roller arranged helically insuch a manner that the channels extend, from the press zone, obliquely downwardly and outwardly. The channels, which preferably extend from the upper to the lower end of each 45 roller, need not each per se extend all around the circumference of the roller but only for a portion of the complete circumference of the roller, in which case each roller will be provided with a plurality of channels separated from each other. 50

Connected to the one vertical side of the pair of rollers is a feed hopper 3 which tapers downwardly to the shape of a wedge. When the press material is charged into the hopper either continuously or periodically, the press material will 55 Preferably pass under the influence of its own weight or through an additional pressure in between the press rollers I and is distributed from below and upwardly'as far as the quantity of press material will permit.

By feeding in the press material in this manner the advantage is derived that the material'which at each moment is pressed between the rollers will be lying tightly together along the press zone and not with intermediate spaces which, on the other hand, will often be the case with horizontal rollers, where the separated water will thus be given an opportunity to enter, with a disadvantageous effect, the intermediate spaces, whence it penetrates through the press zone so as to again combine with the material on the other side of the press zone.

The water separated by means of the vertical rollers provided with oblique channels according to the invention will immediately be free to quickly pass downwardly and at the same time outwardly, from the press zone. During the pressing operation the rollers should rotate comparatively V slowly and the rotational speed shall, as already set forth, be so adapted relatively to the pitch of the channels that the water which is guided laterally outwards on both sides of the press zone will not have time to flow back inwardly before it has been entirely discharged downwardly through the channels and has left the rollers at their lower ends.

To prevent clogging of the channels there may be arranged scrapers, brushes or the like externally on the same. Figs. 3 and 5 of the drawings show such scrapers 5 externally arranged.

To subject the press material to repeated pressing operations, two or more pairs of rollers I with feed hoppers, 3 may be arranged in series according to Fig. 4, so that the press material treated by a pair of rollers will fall directly from the upper pair of rollers along a bridge 4 or the like onto the lower situated pair of rollers, to be subjected to a repeated pressing operation.

.Such repeated pressing is also effected by the arrangement shown in Fig. 5 where a screen 6 is provided between the two outer ones of the three rollers, said screen being concentric with the intermediate roller and situated at a certain distance therefrom. The material treated by the pair of rollers I is carried by the screen over to the press zone and through the same between the intermediate roller I and the outer roller I.

InFigs. 6 and '7, I designates the vertical press rollers, 2 the channels of the rollers, and 3 the feed hopper arranged in front of the press zone. Arranged in the lower part of the hopper is the feed roller 8 which conveys the press material inwardly toward the press zone. Arranged tanpoint toward the press zone. I and II are the roller shafts, of which the shaft II is journalled in bearings I2 rigidly connected with the machine frame I5, while the roller shaft I0 is journalled in bearings I3 which are movable laterally toward and from the bearings I2. The bearings I3 are rigidly connected with the two push rods I4 which are displaceable longitudinally to and fro in the machine frame I5, in the bearings I2 rigidly connected therewith. The rods I4 pro- 10 ject outside the one side of the machine frame (the right-hand side according to Fig. 6) and enter casings I6 rigidly connected with the frame,

' within which casings the rods I 4 are provided with plungers (not shown) actuated by springs enclosed within the casings I6 or by a hydraulic pressure prevailing'therein. This pressure tends to displace the rods I4 to the left (Fig. 6), so that the rollers I are caused to bear powerfully against each other in the press zone.

The driving power is taken off the shaft I! having secured thereon the worm I8 engaging the worm wheel I9. The latter is attached to the fixedly journalled roller shaft I I. From the latter, movement is transferredto the roller shaft I 6 through the gear Wheels 20 and 2 I. The teeth of these wheels are deep enough to prevent the wheels from. coming out of mesh even if the rollers 2 are separated by reason of some or other solid body that may enter between the same.

What we claim is:- a

l. A press of the class described for separating water fronywatery material or the like comprising substantially vertically disposed coacting press rollers having circumferential channels extending obliquely downwardly and outwardly from the press zone between the rollers, the angle betweenthe axes of the rollers and the channels being such that each channel extends from endv to end of the rollers in less than a complete convolution of the channel whereby to provide means for promoting the discharge of the water during the pressing operation and prevent the extracted water from returning to the press zone.

2. A press of the class described for separating water from watery material and the like comprising a pair of substantially vertically disposed coacting press rolls having helically extending channels, one of the rollers having right handed and the other left handed channels extending obliquely downwardly and outwardly from the press zone between the rollers, the angle between the axes of the rollers and the channels being such that each channel extends from end to end of the rollers in less than a complete convolution of the channel whereby to provide means for promoting the discharge of the liquid downwardly and outwardly on both sides of the press zone during the pressing operation.

KARL GUSTAF HELLNER. AXEL GUSTAF J OHANSSON. 

